The top iMac at 1,799 runs on an 800mhz G4, the 1,699 Power Mac run on a 733mhz G4, iMac has 256mb of Ram, Powermac, 128, iMac has a 60 Gb harddrive, PowerMac has a 40, iMac has a SuperDrive, PowerMac has CD-RW, iMac comes with a flat panal 15in Moniter, PowerMac has no moniter, not to mention...